Filler elements for filling containers, and especially for filling bottles with liquid contents, for example with beverages, are known. It is also known to provide a filling-height-controlling element that extends into the container during filling and that controls the filling height of the filling contents in the container. An example of such an element is a rod-shaped probe with at least one electrical probe contact. Another example is a Trinox tube or a return-gas tube.
It is also known to control filling height by adjusting an axial displacement of the filling-height-controlling element. The filling-height-controlling element in this situation is guided through the filler element housing of the filler element and out of the housing at a housing-passage area.
In order to avoid having dirt or germs penetrate via the housing-passage area, it is known to have a protection space in the filler element adjacent to the housing-passage area to accommodate a part of the length of the filling-height-controlling element. During the filling operation, this protection space is subjected to the pressure of an inert gas and separated, by a seal, from a volume that is being protected. The seal is located at a lower end of a tube section that forms the protection area. The tube projects above the dispensing opening of the filler element.
During the filling operation, the filling-height-controlling element is conducted through the seal in a sealed manner. For CIP cleaning, the filling-height-controlling element moves upwards and out of the seal. This forms a fluid connection for a fluid CIP medium into or out of the protection space.
One disadvantage of the above arrangement is that the seal arrangement at the lower end of the tube section that forms the protection space projects into a container during filling.
One solution is an extension that connects to a chamber in the filler element housing. The extension's axial length corresponds at least to the displacement travel range to be formed as a protection area for the filling-height-controlling element. A seal is then provided at this element. During axial adjustment of the filling-height-controlling element, the seal is moved in the extension within an adjustment travel range. The seal, being in the form of a piston, separates the protection area, which is formed inside the extension and above the seal, from the chamber that is produced with a cross-section enlarged in relation to the extension, and that, during the filling is a part of the gas channel for conducting process gases.
For CIP cleaning or for a CIP mode of the filler element, i.e. for creating a CIP flow channel, which includes the chamber and its extension, the seal is moved into the chamber in an opening travel, in order to open the fluid connection between the chamber and the extension. A disadvantage of these filler elements, however, is that the respective CIP flow path through the filler element can only be established after the opening of a further control valve provided at the filler element.